In the business world, “piggyback marketing” is a strategy in which one company agrees to allow distribution or advertising of a second company’s products or services free of charge in a type of partnership arrangement. The advantage to the first company is that it benefits from the added content and from being able to offer an expanded range of complementary products or services to its customers. The advantage to the second company is obvious — it can use the (usually larger) distribution network of the first company to gain new leads, sales, or subscribers it otherwise would not have been able to reach.

This piggybacking principle can also be applied to the SEO efforts of webmasters and bloggers like me who need more backlinks in order to have our pages ranked relatively well in the search engines. It works by acquiring links to your site from established authority sites that have already built up trust and are having their content and links indexed regularly.

I picked up on this technique a few months ago when I noticed that a few of my pages had attracted some natural backlinks from forums and Q&A (question and answer) types of sites where people had posted a link to my page as a reference source. Interestingly, these happen to be the same pages where I am now receiving some of my best search engine rankings.

Upon investigating further and drawing from my experience, I noticed that some of these authority sites were actually competing with my pages in the search results for various keywords. I also see them pop up fairly frequently whenever I do keyword research to determine the viability of a keyword — that is, looking at the overall search volume and the number of competing pages for the exact match phrase.

Although one might expect that getting backlinks from them would be difficult (and perhaps expensive, if you decide to go that route), this is not necessarily the case. Many such sites have some type of free registration system and will allow you to post your own links as long as you’re willing to contribute to the site’s content and are not too spammy about it. For the remainder of this article, I will summarize some of these potential backlink sources below so that you can get some ideas about what is possible.

Answers.Yahoo.com: The Yahoo Answers site is one of the first places where I started seeing some natural backlinks showing up. People were trying to answer questions that someone else had posted, and instead of typing out a detailed answer, they simply posted the link to one of my pages as an information source. You can do the same thing of course, but this time you can speed up the process by seeking out specific topical questions that your site’s content can answer and then posting a link to your site as part of your response. All you need to start posting here is a Yahoo ID. If you’ve been on the Internet for any significant length of time, chances are you already have one. But even if you don’t, the registration is still free.

eHow.com: This site has given me the most headaches overall in terms of SERP competition, even more than the dreaded Wikipedia. As the name implies, it focuses on “how to” topics, and since this genre happens to be one of my favorites as well, I often see the domain in the top 10 results whenever I am doing keyword research for an article that I want to write. Taking a page from the “if you can’t beat ‘em, join ‘em” playbook, I finally decided to register for eHow last night. In addition to being able to post backlinks to your site in the “Resources” section of articles that you publish, there is a “Writer’s Compensation Program” that allows you to earn money for your articles directly by sharing the ad revenue. It seems that eHow also has a social component; you can add friends, send them messages, create a profile, and add a photo of yourself or your business logo. In less than 24 hours since joining, I have had 19 people add me to their friends lists even though I have not done anything with the site yet except for the free registration.

Squidoo.com: I have already dealt with this one in yesterday’s post about the benefits of Squidoo for Internet marketing. You can create your own pages here with a relatively high degree of freedom, including placing backlinks to your site and even links to your favorite affiliate pages. If you don’t feel like doing lots of writing, you can also acquire pages from other users.

AssociatedContent.com: This is a site that functions much like an article directory and will even pay you for submitting articles. You can place links in the “Resources” section. I actually managed to gain a free backlink from here when one of the Associated Content authors wrote an article about bum marketing and linked to one of my pages as a relevant source.

Digg.com, Reddit.com, and many others: Sites in this category are known as social bookmarking or social media sites, and they can be a good source of backlinks as long as you don’t go overboard with self-promotion. The usual routine is to submit your URL, a newsworthy title, some tags, and a short description of the article or news story you wish to publish. After submission, other users will vote it up or down; it’s possible to receive a significant amount of raw traffic at this point if your story does particularly well with the site’s audience. Even if your article never reaches critical mass, however, most of the time the link to your page will remain in an “older stories” or “archive” section somewhere and will still be counted by the search engines.

UsFreeAds.com: This is actually a classified ad site, but it can also be used much like an article directory, allowing you to use keyword-rich text and links. As the name implies, it’s free to post standard ads, but if you upgrade to the Gold Membership (the cost is $10 per year), you can also include direct affiliate links in your article text and have many more ads running on the site at one time. The domain does relatively well in Google and can be a decent source of referrer traffic if you do a reasonably good job of writing your ad copy.

EZineArticles.com, GoArticles.com, Buzzle.com, and many others: These are bona fide article directories. They are free to join but most will not pay you directly for your articles. Instead, you are allowed to place a few lines which are collectively known as a “resource box”, “bio box”, or “about the author section” at the end of your article. Here you can place at least one link to your site and can usually choose your anchor text. Some directories will even allow you to place affiliate links in your resource box; for those that do not, you can link to a page on your site where your favorite affiliate link is strategically placed within some relevant content. This will help your site in terms of SEO and can also bring you significant traffic from the directory sites themselves if your article is sufficiently popular.

Of course there are many other sites that can be used for this type of backlink piggybacking strategy, but the ones listed above have been known to work well and have a PageRank that ranges from 5 to 9. All of these venues will allow you to essentially place your own backlinks for free. The only major cost is the time required to become familiar with the sites, write articles where needed, and make the submissions.

Another possible disadvantage is that many of these sites will tag your links with rel=’nofollow’ (although most traditional article directories will not), which may reduce your PageRank benefit somewhat. However, these links can still be counted for relevancy, content indexing, and anchor text; moreover, many search engines are unaffected by nofollow anyway.